However, these studies did not monitor proximate pharmacodynamic events (such as might occur within hours of drug exposure), and link these to downstream effects, including clinical activity and toxicity. Our hypothesis is that the proximate effects of these drugs (including drug induced changes in F-actin) and early phosphorylation events will be sensitive and quantitative surrogates of subsequent effects including activation of tumor antigen specific T cells as well as innate immune cells. Understanding the correlation between pharmacodynamics of these effects with downstream activation using quantitative assays will facilitate rational development of these agents as immunomodulatory drugs in diverse settings and may also allow optimization of drug delivery to both reduce potential toxicity, and enhance efficacy.